Within a prioritized queuing system there is a sub-priority system that is user defined, represented by column N in the screen shots. Values within N range from 0 to -100 in this example, where the lower the value the lower the priority within the queue. A sub-priority system ensures a calculation is performed sequentially.

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What is a Queue?

When the server is flooded with more jobs than its optimal capacity, surplus jobs are stored in a queue within the head node. Each node has an optimal capacity of 2 jobs, one for each processor.

 

 

 

The screen shot below at "11.28" (pm) shows the job that was at the top of the queue, job no. 3372, at 6.40pm has now entered the cluster at node 15.

 

The screen shots on this page represents an XML output of the "qstat -f" command. The clock is a floating icon and gives an indication for the duration of each job. The load in question mostly comprises a parallelised phylogenomics calculation of the three trypanosomatid genomes.

The screen shot below at "6.40"(pm) shows the 32 processors of the machines full to capacity, together with a subsection of the most prioritized jobs pending in a queue.

 

 

 
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Comments and enquiries Last updated 28th July, 2005 MWG.